The invention relates in general to fuel injectors for internal combustion engines and in particular to fuel injectors that include an orientation feature for orienting the fuel injector with respect to the manifold or head of the engine.
Engine emission requirements have driven the need to achieve better targeting of the fuel spray as it exits a fuel injector. The ability to maintain a consistent and accurate fuel spray targeting at the intake valve depends, among other things, on the stack up of tolerances between the injector fuel orientation and the intake valves.
In the past, the feature that maintains orientation of top feed fuel injectors with respect to the intake valves was located at the fuel inlet end of the injector. Typically, the orientation feature was part of the overmold. The orientation feature on the overmold mated with an orienting clip. The orienting clip mated with an orienting cup on the fuel rail. Such an arrangement is shown, for example, in U.S. Pat. No. 5,803,052 issued on Sep. 8, 1998 to Lorraine et al. The aforementioned U.S. Patent is hereby expressly incorporated by reference.
Thus, in the prior art, the various tolerances between the injector fuel orientation and the intake valves included the tolerance on the injector between the fluid orienting disc and the fuel inlet end, the tolerance between the fuel inlet overmold and the clip, the tolerance between the clip and the rail cup, the tolerance between the rail cup and the rail body, the tolerance between the rail body and the brackets, the tolerance between the brackets and the screw, the tolerance between the screw and the hole in the manifold or head, and the tolerance between the screw hole boss and the intake valves.
Because of the large number of components and tolerances involved, it was difficult to obtain precise targeting of the fuel spray.
It is an object of the invention to provide an apparatus and method to minimize the variation in fuel spray targeting.
It is another object of the invention to provide an apparatus and method to decrease the number of components involved in orienting the fuel spray from a fuel injector.
It is a further object of the invention to provide an apparatus and method to decrease the tolerances involved in orienting the fuel spray from a fuel injector.
It is still a further object of the invention to provide an apparatus and method wherein the fuel injector is directly oriented to the manifold or head.
It is yet another object of the invention to provide an apparatus and method that results in a higher quality, more reliable fuel injector system.
These and other objects of the invention are achieved by a top feed fuel injector for an internal combustion engine comprising a housing; a fuel passage within the housing; an electrically controlled valve mechanism for controlling fuel flow through the fuel passage; and a radially extending protrusion on the housing, the radially extending protrusion configured to mate with a void in one of a manifold or head in which the fuel injector is inserted such that the fuel injector maintains an orientation with respect to the one of the manifold or head.
Another aspect of the invention is an apparatus comprising a fuel injector for an internal combustion engine, the fuel injector including a radially extending protrusion; and one of a manifold or head defining an opening into which the fuel injector is inserted, a wall of the opening defining a void for receiving the radially extending protrusion of the fuel injector such that the fuel injector is oriented with respect to the one of the manifold or head.
Another embodiment of the invention is a top feed fuel injector for an internal combustion engine comprising a housing; a fuel passage within the housing; and an electrically controlled valve mechanism for controlling fuel flow through the fuel passage; wherein the housing defines a radially inwardly extending opening, the radially inwardly extending opening configured to mate with a protrusion on one of a manifold or a head in which the fuel injector is inserted such that the fuel injector maintains an orientation with respect to the one of the manifold or head.
Yet another embodiment of the invention is an apparatus comprising a fuel injector for an internal combustion engine, the fuel injector including a housing defining a radially inwardly extending opening; and one of a manifold or head defining a second opening into which the fuel injector is inserted, a wall of the second opening including a radially extending protrusion which is inserted in the radially inwardly extending opening of the housing of the fuel injector such that the fuel injector maintains an orientation with respect to the one of the manifold or head.
The invention also encompasses a method comprising providing a fuel injector for an internal combustion engine, the fuel injector including a radially extending protrusion; providing one of a manifold or head defining an opening into which the fuel injector is inserted, a wall of the opening defining a void for receiving the radially extending protrusion of the fuel injector; inserting the fuel injector into the opening in the one of the manifold or head; and orienting the fuel injector with respect to the one of the manifold or head by inserting the radially extending protrusion of the fuel injector into the void in the wall of the opening.
A further method of the invention comprises providing a fuel injector for an internal combustion engine, the fuel injector including a housing defining a radially inwardly extending opening; providing one of a manifold or head defining a second opening into which the fuel injector is inserted, a wall of the second opening including a radially extending protrusion; inserted the fuel injector into the second opening; and orienting the fuel injector with respect to the one of the manifold or head by inserting the radially extending protusion of the wall into the radially inwardly extending opening of the housing of the fuel injector.
Further objects, features and advantages of the invention will become apparent from the following detailed description taken in conjunction with the drawing.